A new calibre of systems, generically denoted as RT-MACS, has been designed and developed for the monitoring, analysis and potential control of hydraulic fracturing treatments in real-time during the field operation. A number of prototypes have been built, based on state-of-the-art computer hardware, ranging from super minicomputers to entirely portable systems. They perform the complete spectrum of functions: data-acquisition from calibrated sensors, data-processing and storage in the central facility, display of processed data on scrolling windows, simulation of the overall process, using realistic engineering models for analysis, and display of overall status, including model results. The models used are unique in many respects: they use real-time data as input; they employ a novel history-matching scheme to determine elusive reservoir and fluid parameters in real-time; and they use the most advanced threedimensional analysis to make calculations for pressures, height, width and length of fractures. Both trailer-transported and portable system prototypes have been suc-cessfully implemented in a number of commercial field operations, running without disruption in standard jobs on cooperative wells provided by interested producing com-panies; their presence had sufficient practical impact that the portable systems are now being offered on a broader scale throughout the industry.